decent magnification for saw sharpening?

[Jessica Pierce-LaRose]

A fair amount of threads about saw sharpening here lately, so I don't know where to add this, but I'm curious what folks are liking for magnification when working finer-toothed saws? Realizing a couple of my finer saws need a touch up, and that I probably could use some help with the eyesight doing that. Something about the saw sharpening is just a little tougher for me to focus on than the soldering I do on electronics. (which is good because the magnifier on my "helping hands" thing is scratched to all heck)

The things I've used in the past were all pretty junky - lenses that came scratched and scratched more just looking at them, and offered sort of a ripply image from poorly ground lenses. Terribly uncomfortable head visors that broke apart after a week, things like that.

So I'd like to buy a quality . . . something. For folks that use these things, what do you like? Any suggestions on where to get a quality one, so I don't end up with another piece of junk?

[Ryan Baker]

I can't help much with a magnifier recommendation, because I haven't found one I particularly like. The articulating lamps that are a big magnifier lens surrounded by a ring light aren't too bad.

But another thing that you might find helpful is to color the teeth with a marker or machinists' layout fluid. That makes it a lot easier to see where you are working, and when you have filed enough.

[Paul Saffold]

Well this is not expensive and will probably scratch easily but I've been careful with them so no scratches. They are Carson +4 diopter clip-on. They flip up/down as needed. I wear progressive glasses and could not use the head set style. I couldn't get them down far enough to help. They are 2x magnification. They do have a narrow depth of focus. I bought them in a mall but here is a link. http://www.amazon.com/Carson-Optical-Clip--Magnifying-Diopters/dp/B00014VX1A/ref=sr_1_1?ie=UTF8&qid=1350350389&sr=8-1&keywords=Carson+%2B4+diopter

[Charlie Buchanan]

I use a 2.5x Donegan binocular magnifier. I'm happy with the magnification and working distance. Got it from Amazon for less than $30 as I recall. The lenses are interchangeable but the 2.5x works for me. Lie-Nielsen sells a different brand for $24.

[Bryan Ericson]

Tools for Working Wood and Lee Valley both sell magnifiers as well.

I'm also casually looking for some sort of magnifier for saw sharpening, but I'm not in any particular rush. I think I'll go with the type you wear on your head, because it seems like that would be the most useful for other things in addition to saw sharpening. One thing to be careful of is to not get too high of a magnification. If the magnification level is high, the focal length will be short and you'll need to lean in pretty close or else the image will be blurred. Also, if you have a choice of lens material, be sure to get ones with glass lenses as opposed to acrylic lenses - the glass resists scratches and has less distortion around the periphery.

I've read good things about the Donegan Optivisor magnifiers - comfortable, lightweight, good quality. They are available with glass lenses, I think.

[Tom Blank]

Joshua,

I have good luck with the OptiVisor. http://www.doneganoptical.com/products/optivisor I have a 1.75x and a 2.75x lens, but use the 1.75x the most. You really have to get your nose into whatever you are working on with the 2.75x.

The lenses are optical glass.

HTH,

Tom

[Jim Koepke]

Joshua,

You do not mention whether or not you normally wear glasses. I do, so the clip ons that Paul mentioned are something that I have tried. Mine came from Michael's art supply. They are in with the needle point supplies.

Another trick that seems to work is using a pair of reading glasses worn over my bifocals helps.

Good lighting helps in more ways than one. The extra light will contract your pupils which helps to sharpen your vision.

jtk

[george wilson]

I just wear 4X drugstore glasses for the tiny work I do. Can't stand optivisors,and magnifying lamps are a nuisance. The eye glasses are easiest to use. It is a little hard to find over 3.75X in drug stores. There's 1 place here that sells them. I'm sure they could be found online.

[David Keller NC]

Joshua - I use reading glasses (+1.5X magnification, but I think that the optimum would vary with the individual). Besides the reading glasses, though, the item that helps the most is a high-intensity LED headlamp of the type that are sold for backpackers/campers.

This is a personal preference, but I have a somewhat expensive Petzl-brand Tika XP 2:

http://www.petzl.com/en/outdoor/headlamps/universal/tikka-xp

You can get inexpensive ones at Target or Wall-Mart for about $10, but I've found that those tend to be a lot heavier, the intensity of the lamp isn't as great, the elastic band doesn't hold up, and the ratchet mechanism that postions the light gives way very quickly.

[Chris Griggs]

Sheesh, I can't believe I've never thought to use plain ole reading glasses. Maybe I never thought of because I've never had glasses before, but seriously how did that never occur to me? I keeping saying to myself "one of these days I order one of those visor things". All I needed to do was walk down to the drugstore on the corner. Thanks for the great idea George and David.

[Don Jarvie]

I use the Optivisor and really like it. I wear glasses so I like just flipping it down. I bought them for when I did fine work like dovetails but now I find I'm using them more for other things. Once I put them on I leave them on and don't even notice them.

[Chris Griggs]

I just wandered over to CVS on my lunch break and found these (http://optical.cvs.com/Accessories/Reading-Glasses/18392/Light-Specs-Reading-Glasses.html?CategoryID=5) reading glasses with built in LEDs. They had them in 1.5x, 2.0x, 2.5x. The 2.0x seemed about right in terms of a happy medium of magnification and distance from and object while in focus.

At $25 not really any cheaper than a visor, but I guess the built in LEDs would save one from having buy that separately (assuming they last more than a week).

Seems like a nice solution in terms of adding light and magnification pretty unobtrusively.

[Caleb James]

What about a Dazor (U.S) or Luxo (Norway)? The price may be higher than you may want but I imagine there would be no concerns about the quality?

[Halgeir Wold]

I work with electronic systems in my day job, and have been using the OptiVisor for over 10 years, - it is by far my most important tool these days.....
I also use regular glasses, and usually balances the glasses on my nosetip, and the OptiVisor above.... :-)
Takes a while to get used to, though.......

EDIT: I also have a Luxo on my work bench, and while good as it is, I just can't do without the OptiVIsor

[Mike Allen1010]

I have both adjustable arm lamp with built-in magnifying lens and a magnifying visor.

I prefer the visor (which I use with a separate adjustable arm worklight), because it's faster and easier for me to just move my head as I move down the saw from tooth to tooth, rather than moving the magnifying arm/lens.I can also wear glasses under the visor no problem.

The visor I have has a 2.2x fixed lens and a second flip down lens which provides 3.3x there is also a third flip down monocle that provides magnification up to 4.8 times that I rarely use. The link below shows a picture:

http://www.discountcasinogear.com/Trademark-ToolsT-Magnifying-Visor-with-LED-Li-p/75-mg9002.htm?Click=13965&gclid=COfHkfDEiLMC

Whatever kind of magnification you decide on, if you work on saws with more than 8 PPI I would encourage you to get at least 3X magnification. During final sharpening it will allow you to clearly see the very small flats that result from final jointing. You want to file just enough to make these flats disappear to get the sharpest possible cutting edge while still maintaining the consistent set and tooth height established in previous sharpening steps.

If you're going to be restoring/sharpening any saws that have been badly neglected (as opposed to just touching up a saw that as already been correctly sharpened), consider buying your files by the box. As you can see in the photos below, the initial step of of reestablishing the correct tooth height/profile removes a lot of metal and can really burn through files.

243480243481

When sharpening a typical 26", 8-10 PPI vintage saw with high-quality steel, I typically go through 2-3 Grobet files for the entire process of profiling the teeth, jointing, filing the fleam angle, setting, final jointing and final sharpening. Nothing worse than getting three quarters of the way through sharpening a saw and running out of the files you need!

I recently did my own nonscientific comparison of the following types of saw files while restoring/sharpening nine full-size vintage saws: Pherd, Grobet (their "imported" files -- not sure where they're made. For this comparison I didn't include the Swiss made Grobet's which IMHO are excellent but expensive), Nicholson (current made in Mexico), Nicholson (vintage made in the USA) and Bahco (thank you Mark Wyatt!).

I switched among the various types of files on a single saw (for an apples to apples comparison) and counted the number of strokes needed per tooth and the number of teeth I was able to file before the edge became too dull to work effectively. I cleaned all the files regularly with a file card.

The saw plates range from extremely hard (Simmons #72) to moderate (Disston D-8) to relatively soft (1870s era Disston #7). As an example of the differences between the steel the Mexican Nicholson wouldn't even cut the Simonds plate and the apex of the file disintegrated almost immediately, while the same type of file was usable on the Disston #7 cast steel.

I evaluated the files based on their speed of cut (number of strokes needed per tooth), durability (number of teeth filed before the edge became dull) and to a lesser degree on the quality of the finished tooth surface -- most of the time if the file is still cutting it leaves a clean, smooth tooth surface, however if you're really bearing down trying to squeeze out the last few teeth from dull file it can leave a rougher finished surface.

Based on these criteria my own subjective impressions I rated the files as follows on a scale of 1 to 10:

Nicholson USA - 10
Grobet - imported 7
Bahco - 6
Pherd - 5
Nicholson Mexico - 0

I'm probably shooting myself in the foot here, but in summary if you can find any NOS USA made Nicholson (or Simonds) files-- their awesome, but hard to find.

The Grobet's are my "go to" file based on a combination of price and performance but it seems like their availability is inconsistent (I get mine when I can on Amazon). Hopefully now that they're available from Lee Valley supply will be better.

Admittedly have the least amount of experience with the Bahco, I only had a couple individual files while I've used boxes of the others. I will definitely try another box.

I was little bit disappointed with the Pherds. They are made in Germany, not cheap and I'd hoped for good things. However the two boxes I have were strangely inconsistent from file the file-- some were every bit the equal of the Grobet's, but others dulled very quickly in premium steel.

I'm not an engineer, I don't do much metalworking, and this wasn't a quantitative scientific test, but have sharpened lots of saws and wanted to pass along my observations in the hope they may be of interest to some of the sawyers here in the Cave.

All the best, Mike